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It is a Hardie 1" valve. Sorry but I don't know any more specifics.

4 of 5 zones are working perfectly. When zone 5 is turned on there is a "thumping" sound in the pipes, low pressure out of the rotory sprinkler heads, and the main water supply pipe shakes (it is above ground with a manual shut off valve in-line). I took the bleeder valve completely out of the valve and the thumping stopped and the pressure came back. When the bleeder valve is back in the thumping starts again and the pressure decreases. Any ideas?